<template>
  <div class="todo-footer">
    <label>
      <input type="checkbox" v-model="checkAll" />
    </label>
    <span>
      <span>已完成{{ oktodo }}</span> / 全部 {{ todoList.length }}
    </span>
    <button class="btn btn-danger" @click="deleteAllhandle">
      清除已完成任务
    </button>
  </div>
</template>

<script>
export default {
  name: "Footer",
  props: ["todoList"],
  //计算属性
  computed: {
    //统计已完成的
    oktodo() {
      return this.todoList.reduce((p, c) => {
        return c.done === true ? p + 1 : p;
      }, 0);
    },
    checkAll: {
      set(value) {
        this.$emit("checkAllHadnle", value);
      },
      get() {
        //使用数组方法every 只有当所有都为ture 才返回ture 当有一个false 则直接返回false
        return (
          this.todoList.every((item) => item.done) && this.todoList.length !== 0
        );
      },
    },
  },
  methods: {
    deleteAllhandle() {
      this.$emit("deleteAllhandle");
    },
  },
};
</script>

<style scoped>
/*footer*/
.todo-footer {
  height: 40px;
  line-height: 40px;
  padding-left: 6px;
  margin-top: 5px;
}

.todo-footer label {
  display: inline-block;
  margin-right: 20px;
  cursor: pointer;
}

.todo-footer label input {
  position: relative;
  top: -1px;
  vertical-align: middle;
  margin-right: 5px;
}

.todo-footer button {
  float: right;
  margin-top: 5px;
}
</style>
